By RAY FLEMING PRESIDENT Bush's reluctance to move quickly to bring to an end the fighting and human suffering in Liberia is inexplicable - except in terms of the narrow self-interest of the United States. The arguments for intervention are these: that no nation in Africa has a better historical claim on America's help than Liberia which was founded in 1821 by freed American slaves; that hundreds of innocent people are being killed and seriously wounded in the fighting and that thousands may die from cholera and dysentery as a result of the lack of fresh water; that the government and people of Liberia want American intervention and that the fighting between the government and rebel forces is unlikely to be ended without it; and that the promised Nigerian force will take at least two weeks to arrive. The arguments against intervention appear to be these: that President Bush insists on the incumbent President of Liberia, Charles G Taylor, standing down before the United States will intervene; that the Pentagon believes even a small force of 2'000 troops would over-stretch the Army's overseas commitments; that the loss of American lives in a country where the US has no direct interest (unlike Iraq) would not be acceptable to the American public; that it would be easier to go in than to get out; and that any US involvement should follow, not precede, a presence of forces from the region. The arguments for delaying action are largely selfish. In similar circumstances Britain intervened effectively in Sierra Leone. The US should follow that example.